Urine protein analysis by gel electrophoresis and laser densitometry after chemotherapy in pediatric cancer patients.

A common side effect of chemotherapy is reversible or nonreversible nephrotoxicity. SDS polyacrylamide gel electrophoresis combined with laser densitometry was evaluated as a suitable method to analyze pathologic urine proteins. A total of 52 pediatric patients were followed during and 63 patients were followed after therapy. During therapy renal damage was recorded in 43% of the leukemia patients, in 56% of nephroblastoma patients, and 75% of patients with other tumors. Three or more months after therapy pathologic patterns were seen in 25% of acute lymphoblastic leukemia patients, in 35% of patients with nephroblastoma, and in 62% of other patients. Patients with persistent complete tubular proteinuria and mixed glomerular/tubular proteinuria were found to have a high risk for irreversible renal damage and should be controlled periodically. This method permits a rapid and reliable analysis of urine proteins and is suitable for follow-up tests of renal function during and after chemotherapy.